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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) $ in Thousands | Mar. 31, 2019 USD ($) subsidary | Jan. 01, 2019 USD ($) | Mar. 31, 2018 USD ($)
--- | --- | --- | ---
Property, Plant and Equipment [Line Items] |  |  |
Number of subsidiaries | subsidary | 6 |  |
Operating lease liability | $ 11,610 |  |
Operating lease right of use asset | $ 11,600 |  |
Accounting Standards Update 2018-02 |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Operating lease liability |  | $ 12,000 |
Operating lease right of use asset |  | $ 12,000 |
Accumulated Other Comprehensive Loss | Accounting Standards Update 2018-02 |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Reclassification of certain tax effects from accumulated other comprehensive income |  |  | $ 486
Retained Earnings | Accounting Standards Update 2018-02 |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Reclassification of certain tax effects from accumulated other comprehensive income |  |  | $ 486

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- Definition Present value of lessee's discounted obligation for lease payments from operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details
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